ffmpeg API录制rtsp视频流

来源：互联网发布：时间机器字幕制作软件编辑：程序博客网时间：2024/05/01 12:27

原文出自http://blog.csdn.net/zxwangyun/article/details/8190638#reply 作者 Sloan

这里在录制时，并没有进行转码，只是相当于把rtsp视频直接保存到一个文件中。

[cpp] view plaincopyprint?

#include <stdio.h>
#ifdef __cplusplus
extern "C" {
#endif
#include <libavcodec/avcodec.h>
#include <libavformat/avformat.h>
//#include <libswscale/swscale.h>
#ifdef _MSC_VER
int strcasecmp(const char *s1, const char *s2)
{
while ((*s1 != '\0')
&& (tolower(*(unsigned char *) s1) ==
tolower(*(unsigned char *) s2)))
{
s1++;
s2++;
}
return tolower(*(unsigned char *) s1) - tolower(*(unsigned char *) s2);
}
int strncasecmp(const char *s1, const char *s2, unsigned int n)
{
if (n == 0)
return 0;
while ((n-- != 0)
&& (tolower(*(unsigned char *) s1) ==
tolower(*(unsigned char *) s2))) {
if (n == 0 || *s1 == '\0' || *s2 == '\0')
return 0;
s1++;
s2++;
}
return tolower(*(unsigned char *) s1) - tolower(*(unsigned char *) s2);
}
#endif //_MSC_VER
#ifdef __cplusplus
}
#endif
/***********************************************************
'** stream_component_open
* Description:
* //open the stream component for video/audio
*
*
* Params:ic-pointer which contains the url and codec details
:stream_index-index denoting video or audio stream
***********************************************************/
int stream_component_open(AVFormatContext *ic, int stream_index)
{
AVCodecContext *enc;
AVCodec *codec;
if (stream_index < 0 || stream_index >= (int)ic->nb_streams)
return -1;
enc = ic->streams[stream_index]->codec;
/* prepare audio output */
if (enc->codec_type == CODEC_TYPE_AUDIO)
{
if (enc->channels > 0)
enc->request_channels = FFMIN(2, enc->channels);
else
enc->request_channels = 2;
/*Hardcoding the codec id to PCM_MULAW if the audio
codec id returned by the lib is CODEC_ID_NONE */
if(enc->codec_id == CODEC_ID_NONE)
{
enc->codec_id = CODEC_ID_PCM_MULAW;
enc->channels = 1;
enc->sample_rate = 16000;
enc->bit_rate = 128;
}
}
codec = avcodec_find_decoder(enc->codec_id);
enc->idct_algo = FF_IDCT_AUTO;
enc->flags2 |= CODEC_FLAG2_FAST;
enc->skip_frame = AVDISCARD_DEFAULT;
enc->skip_idct = AVDISCARD_DEFAULT;
enc->skip_loop_filter = AVDISCARD_DEFAULT;
enc->error_concealment = 3;
if (!codec || avcodec_open(enc, codec) < 0)
return -1;
avcodec_thread_init(enc, 1);
enc->thread_count= 1;
ic->streams[stream_index]->discard = AVDISCARD_DEFAULT;
return 0;
}
//声明函数
int enable_local_record(AVFormatContext *ic/*已经打开的视频文件上下文*/,
int videostream,int audiostream,
AVFormatContext **out_oc,const char * ofile,const char * ofileformat);
int exit_onerr(const char * err_desc/*错误描述*/,int err_code/*错误码*/)
{
printf("%s\n",err_desc);
system("pause");//暂停，查看错误描述
return err_code;
}
int main(int argc, char* argv[])
{
//初始化ffmpeg链表结构
avcodec_register_all(); // Register all formats and codecs
av_register_all();
AVPacket packet;
//打开文件
AVFormatContext * ic = NULL;
const char * rtsp_url = "rtsp://192.168.0.168:8557/PSIA/Streaming/channels/2?videoCodecType=H.264";
if(av_open_input_file(&ic, rtsp_url, NULL, 0, NULL)!=0)
{
return exit_onerr("can't open file.",-1);
}
if(!ic)
{
return exit_onerr("unknow error.",-2);
}
ic ->max_analyze_duration = 1000;
//get streams information
if(av_find_stream_info(ic)<0)
{
av_close_input_file(ic);//退出前，记得释放资源
ic = NULL;
return exit_onerr("con't init streams information.",-3);
}
//find stream
int videoStream=-1; // Didn't find a video stream
int audioStream=-1; // Didn't find a audio stream
// Find the first video stream
for(int i=0; i<ic ->nb_streams; i++)
{
if( ic ->streams[i]->codec->codec_type==CODEC_TYPE_VIDEO)
{
videoStream=i;
break;
}
}
// Find the first audio stream
for(int i=0; i<ic ->nb_streams; i++)
{
if( ic ->streams[i]->codec->codec_type==CODEC_TYPE_AUDIO)
{
audioStream=i;
break;
}
}
//判断视频文件中是否包含音视频流，如果没有，退出
if(audioStream<0 && videoStream<0)
{
av_close_input_file(ic);//退出前，记得释放资源
ic = NULL;
return exit_onerr("con't find a audio stream or video stream",-4);
}
//open the stream component for video
int videoComponent = -1;
if(videoStream >= 0)
{
videoComponent = stream_component_open(ic, videoStream);
if(videoComponent<0)
{
av_close_input_file(ic);//退出前，记得释放资源
return exit_onerr("not supported video stream",-5);//要求重新编译ffmpeg以支持该种编码格式
}
}
//open the stream component for audio
int audioComponent = -1;
if(audioStream >= 0)
{
audioComponent = stream_component_open(ic, audioStream);
if(audioComponent<0)
{
av_close_input_file(ic);//退出前，记得释放资源
return exit_onerr("not supported audio stream",-6);//要求重新编译ffmpeg以支持该种编码格式
}
}
//////////////////////////////////////////////////////
int ret = 0;
//初始化并打开录像
AVFormatContext * oc = NULL;
const char * out_file_name = "D:\\test.avi";
//获取一帧完整的图像用于初始化ffmpeg内部的一些结构体数据(这里使用什么数据尚未清楚，请自行查看)，否则会出现写文件头失败
int got_picture = 0;
AVFrame *frame = avcodec_alloc_frame();
while( 1 )
{
if(av_read_frame( ic, &packet)<0)
{
av_free_packet(&packet);
av_close_input_file(ic);//退出前，记得释放资源
return exit_onerr("read frame error.",-7);//读取视频帧失败
}
if(packet.stream_index == videoStream)
{
avcodec_decode_video(ic->streams[videoStream]->codec, frame, &got_picture, packet.data, packet.size);
}
av_free_packet(&packet);
if(got_picture)
break;
}
av_free(frame);
ret = enable_local_record(ic,videoStream,audioStream,&oc,out_file_name,"avi");
if(ret <0 || !oc)
{
//退出前，记得释放资源，现在又多了个oc参数需要释放
if(oc)
{
///cleanup the output contents format
for(unsigned int i=0;i< oc->nb_streams;i++)
{
av_metadata_free(&oc ->streams[i]->metadata);
av_free(oc ->streams[i]->codec);
av_free(oc ->streams[i]);
}
for(unsigned int i=0;i<oc ->nb_programs;i++)
{
av_metadata_free(&oc ->programs[i]->metadata);
}
for(unsigned int i=0;i<oc ->nb_chapters;i++)
{
av_metadata_free(&oc ->chapters[i]->metadata);
}
av_metadata_free(&oc ->metadata);
av_free(oc);
}
av_close_input_file(ic);
return exit_onerr("can't init out file.",-8);
}
//开始录像
int video_dts = 0,audio_dts = 0;//时间戳
int total_frame = 300;//写300帧文件
while(total_frame--)
{
if( av_read_frame( ic, &packet) <0 ) //read the packet
{
//读取数据出错
av_free_packet(&packet);
break;
}
if(packet.data && (packet.stream_index == videoStream || packet.stream_index == audioStream) )
{
//计算时间视频戳，顺序+1，这里可以多研究几种编码的音视频文件，求其时间戳生成格式，h264编码顺序加1即可
if(packet.stream_index == videoStream)
{
packet.dts = video_dts++;
packet.pts = video_dts;
}
else if(packet.stream_index == audioStream)//计算音频时间戳
{
packet.dts = audio_dts++;
packet.pts = audio_dts * (1000 * packet.size /ic ->streams[packet.stream_index]->codec ->sample_rate);
}
packet.flags |= PKT_FLAG_KEY;
if(av_interleaved_write_frame(oc,&packet)<0)
{
printf("st:%d\twrite frame failed.\n",packet.stream_index);
}
}
av_free_packet(&packet);
}
//关闭录像文件和输入文件
//写文件尾
av_write_trailer(oc);
/* close the output file if need.*/
if (!(oc ->oformat->flags & AVFMT_NOFILE))
{
url_fclose(oc->pb);
}
//释放资源
/*cleanup the output contents format*/
for(unsigned int i=0;i< oc->nb_streams;i++)
{
av_metadata_free(&oc ->streams[i]->metadata);
av_free(oc ->streams[i]->codec);
av_free(oc ->streams[i]);
}
for(unsigned int i=0;i<oc ->nb_programs;i++)
{
av_metadata_free(&oc ->programs[i]->metadata);
}
for(unsigned int i=0;i<oc ->nb_chapters;i++)
{
av_metadata_free(&oc ->chapters[i]->metadata);
}
av_metadata_free(&oc ->metadata);
av_free(oc);
av_close_input_file(ic);
return 0;
}
//初始化录像文件，代码较长，可写成函数
/*
*return <0 failed, 0 success
*/
int enable_local_record(AVFormatContext *ic/*已经打开的视频文件上下文*/,int videostream,int audiostream,AVFormatContext **out_oc,const char * ofile,const char * ofileformat)
{
AVFormatContext *oc = NULL;//
AVOutputFormat *fmt = NULL;
if( ofileformat )
{
fmt = av_guess_format(ofileformat, NULL, NULL);
}
if(!fmt)
{
printf("out file format \"%s\" invalidate.\n",ofileformat);
return -1;
}
/*******************************************init output contents begin**********************************************************/
/* allocate the output media context */
oc = avformat_alloc_context();
if (!oc)
{
printf("out of memory.\n");
return -2;//内存分配失败
}
*out_oc = oc;
oc ->oformat = fmt;
sprintf_s( oc ->filename, sizeof( oc ->filename), "%s", ofile);
av_metadata_conv(oc, fmt->metadata_conv, NULL);
if( videostream >=0 )
{
//AVCodecContext* pCodecCtx= ->streams[videostream]->codec;;
//add video stream
AVStream * st = av_new_stream(oc, videostream);
if(!st)
{
printf("can not add a video stream.\n");
return -3;
}
st->codec->codec_id = ic ->streams[videostream] ->codec->codec_id;
st->codec->codec_type = CODEC_TYPE_VIDEO;
st->codec->bit_rate = ic ->streams[videostream] ->codec->bit_rate;
st->codec->width = ic ->streams[videostream] ->codec->width;
st->codec->height = ic ->streams[videostream] ->codec->height;
st->codec->gop_size = ic ->streams[videostream] ->codec->gop_size;
st->codec->pix_fmt = ic ->streams[videostream] ->codec->pix_fmt;
st->codec->frame_size = ic ->streams[videostream] ->codec->frame_size;
st->codec->has_b_frames = ic ->streams[videostream] ->codec->has_b_frames;
st->codec->extradata = ic ->streams[videostream] ->codec->extradata;
st->codec->extradata_size = ic ->streams[videostream] ->codec->extradata_size;
st->codec->codec_tag = ic ->streams[videostream] ->codec->codec_tag;
st->codec->bits_per_raw_sample = ic ->streams[videostream] ->codec->bits_per_raw_sample;
st->codec->chroma_sample_location = ic ->streams[videostream] ->codec->chroma_sample_location;
st->time_base.den = ic ->streams[videostream] ->time_base.den;
st->time_base.num = ic ->streams[videostream] ->time_base.num;
st->cur_dts = ic ->streams[videostream] ->cur_dts;
st->stream_copy = 1;
st->pts.den = ic ->streams[videostream] ->time_base.den;
st->pts.num = ic ->streams[videostream] ->time_base.num;
if( oc ->oformat->flags & AVFMT_GLOBALHEADER)
st ->codec->flags |= CODEC_FLAG_GLOBAL_HEADER;
if(av_q2d(ic ->streams[videostream] ->codec->time_base)*ic ->streams[videostream] ->codec->ticks_per_frame > av_q2d(ic ->streams[videostream]->time_base) &&
av_q2d(ic ->streams[videostream]->time_base) < 1.0/1000)
{
st->codec->time_base = ic ->streams[videostream] ->codec->time_base;
st->codec->time_base.num *= ic ->streams[videostream] ->codec->ticks_per_frame;
}
else
{
st->codec->time_base = ic ->streams[videostream] ->time_base;
}
st->disposition = ic ->streams[videostream] ->disposition;
}
if(audiostream >= 0 )
{
AVStream * st = av_new_stream( oc, audiostream);
if(!st)
{
printf("can not add a audio stream.\n");
return -4;
}
st->codec->codec_id = ic ->streams[audiostream] ->codec->codec_id;
st->codec->codec_type = CODEC_TYPE_AUDIO;
st->codec->bit_rate = ic ->streams[audiostream] ->codec->bit_rate;
st->codec->gop_size = ic ->streams[audiostream] ->codec->gop_size;
st->codec->pix_fmt = ic ->streams[audiostream] ->codec->pix_fmt;
st->codec->bit_rate = ic ->streams[audiostream] ->codec->bit_rate;
st->codec->channel_layout = ic ->streams[audiostream] ->codec->channel_layout;
st->codec->frame_size = ic ->streams[audiostream] ->codec->frame_size;
st->codec->sample_rate = ic ->streams[audiostream] ->codec->sample_rate;
st->codec->channels = ic ->streams[audiostream] ->codec->channels;
st->codec->block_align = ic ->streams[audiostream] ->codec->block_align;
st->time_base.den = ic ->streams[audiostream] ->time_base.den;
st->time_base.num = ic ->streams[audiostream] ->time_base.num;
st->stream_copy = 1;
st->pts.den = ic ->streams[audiostream] ->time_base.den;
st->pts.num = ic ->streams[audiostream] ->time_base.num;
if( oc->oformat->flags & AVFMT_GLOBALHEADER)
st ->codec->flags |= CODEC_FLAG_GLOBAL_HEADER;
if(av_q2d(ic ->streams[audiostream] ->codec->time_base)*ic ->streams[audiostream] ->codec->ticks_per_frame > av_q2d(ic ->streams[audiostream]->time_base) &&
av_q2d(ic ->streams[audiostream]->time_base) < 1.0/1000)
{
st->codec->time_base = ic ->streams[audiostream] ->codec->time_base;
st->codec->time_base.num *= ic ->streams[audiostream] ->codec->ticks_per_frame;
}
else
{
st->codec->time_base = ic ->streams[audiostream] ->time_base;
}
}
/* set the output parameters (must be done even if no parameters). */
//AVFormatParameters params, *ap = ¶ms;
//memset(ap, 0, sizeof(*ap));
if (av_set_parameters(oc, NULL/*ap*/) < 0)
{
printf("invalid output format parameters.\n");
return -5;
}
oc ->flags |= AVFMT_FLAG_NONBLOCK;
/*******************************************init output contents end**********************************************************/
/* open the output file, if needed */
if (!(oc ->oformat ->flags & AVFMT_NOFILE))
{
try
{
if (url_fopen(&oc->pb, ofile, URL_WRONLY) < 0)
{
printf("Could not open file.\n");
return -6;
}
}
catch(...)
{
printf("Could not open file.\n");
return -6;
}
}
/* write the stream header, if any */
if( 0 != av_write_header(oc))
{
printf("write the stream header failed.\n");
return -7;
}
return 0;
}